paliperidone palmitate (Invega Sustenna) Side Effects

What is Invega Sustenna? What is it used for?

Invega Sustenna (paliperidone palmitate) is
an atypical antipsychotic used to treat schizophrenia. It is a long acting form
of paliperidone (Invega). Other atypical antipsychotic drugs include

olanzapine
(Zyprexa),
quetiapine (Seroquel),
ziprasidone (Geodon),
iloperidone (Fanapt),
asenapine (Saphris) and
aripiprazole (Abilify).

Atypical antipsychotics differ from typical antipsychotics because they cause
a lesser degree of movement (extrapyramidal) side effects and constipation.

The exact mechanism of action of paliperidone is not known, but, like other
anti-psychotics, it is believed that paliperidone affects the way the brain
works by interfering with communication among the brain's nerves. Nerves
communicate with each other by making and releasing chemicals called
neurotransmitters. The neurotransmitters travel to other nearby nerves where
they attach to receptors on the nerves. The attachment of the neurotransmitters
either stimulates or inhibits the function of the nearby nerves. Paliperidone
blocks several of the receptors on nerves including dopamine type 2, serotonin
type 2, and alpha 2 adrenergic receptors. It is believed that many psychotic
illnesses are caused by abnormal communication among nerves in the brain and
that by altering communication through neurotransmitters, paliperidone can alter
the psychotic state. Invega Sustenna was approved by the FDA in July 2009.

What brand names are available for Invega Sustenna?

Invega Sustenna

Is Invega Sustenna available as a generic drug?

Do I need a prescription for Invega Sustenna?

Yes

What are the side effects of Invega Sustenna?

The most common side effects include

injection site reaction,
weight gain,
headache,
upper respiratory tract infection,
feeling restlessness
or difficulty sitting still,
stiffness and shuffling walk,
tremors, and
slow
movements.

Less common but serious side effects include:

Increased risk of stroke in elderly patients
with dementia-related psychosis.
Neuroleptic malignant syndrome (NMS). NMS is
a rare but serious side effect associated with the use of antipsychotics. NMS
may result in death and must be treated in the hospital. Signs and symptoms of
NMS may include high fever, sweating (diaphoresis), severe muscle stiffness or
rigidity, confusion, loss of consciousness, high blood pressure, rapid
heartbeat, and changes in your breathing.
Extrapyramidal side effects (EPS) include:
- Dystonia: painful spasms of the oral, throat, or
  neck muscles that may cause problems with speech, swallowing, and stiff neck.
- Akathisia: feelings of restlessness or difficulty
  sitting still.
- Pseudoparkinsonism: drug-induced Parkinson’s
  symptoms.
Tardive dyskinesia (TD). TD usually occurs
after long term use of antipsychotics and usually causes movement problems
affecting the tongue, lips, jaw, face, and extremities.
Metabolic changes including high blood sugar
(hyperglycemia), diabetes mellitus, increase in blood cholesterol, and weight
gain.
High blood levels of prolactin. Prolactin is
a hormone that allows the production of breast milk. High levels of prolactin
may cause menstrual abnormalities, leakage of milk from the breast, development
of breasts in (males gynecomastia), and erection problems in men (erectile
dysfunction).
Seizures

What is the dosage for Invega Sustenna?

Invega Sustenna is administered once every month by a health-care
professional. Invega Sustenna is injected intramuscularly (into the muscle) in
the upper arm or upper buttocks.

The starting dose for schizophrenia or schizoaffective
disorder is 234 mg on day one then 156 mg one week later (day 8) injected into
the upper arm. The monthly maintenance dose is 39 to 234 mg for schizophrenia
and 78 to 234 mg for schizoaffective disorder. Maintenance injections may be
administered into the upper arm or buttocks. The maximum dose is 234 mg monthly.

QUESTION

Schizophrenia is the most disabling mental illness.
See Answer

Which drugs or supplements interact with Invega Sustenna?

Invega Sustenna can cause low blood pressure especially when standing up from
sitting or lying down (orthostatic hypotension). Therefore, Invega
Sustenna
should be used cautiously with other drugs also associated with orthostatic
hypotension.

Paliperidone is metabolized or broken down by liver enzymes. Drugs that
induce these enzymes will increase their activity and consequently decrease
blood levels of paliperidone. Invega Sustenna should not be taken with
carbamazepine (Tegretol), phenytoin (Dilantin), rifampin (Rifadin),
St. John’s Wort, and other drugs that may decrease its blood levels.

Paliperidone blocks the effect of dopamine in the brain while dopamine
agonists such as levodopa (Sinemet) increase the levels of dopamine in the
brain. Combining these agents is not recommended since the effect of both drugs
will be reduced.

Is Invega Sustenna safe to take if I’m pregnant or breastfeeding?

Invega Sustenna is known to enter human milk but its effects
on the breastfeeding infant or milk production is not yet known.

What else should I know about Invega Sustenna?

What preparations of Invega Sustenna are available?

Extended-release injectable suspension: 39, 78, 117, 156, or 234 mg

How should I keep Invega Sustenna stored?

Invega Sustenna should be stored at room temperature between 59 F
and 86 F (15 C to 30 C).